Auxiliary power unit inlet apparatus and methods

Abstract

Auxiliary power unit inlet apparatus and methods are disclosed. An example apparatus includes an air inlet for an aircraft including a first air flow path and a second air flow path. The first air flow path is immediately adjacent the second air flow path. The first air flow path is at least partially separated from the second air flow path by a first panel. The example apparatus includes a door hingably coupled adjacent the air inlet. The door includes a second panel extending from an interior surface of the door to substantially prevent air from flowing across the interior surface between the first air flow path and the second air flow path.

What is claimed is: 
     
       1. An apparatus, comprising:
 an air inlet for an aircraft comprising a first air flow path and a second air flow path, the first air flow path being immediately adjacent the second air flow path, the first air flow path at least partially separated from the second air flow path by a first panel positioned within the air inlet; and 
 a door hingably coupled adjacent the air inlet, the door comprising a second panel oriented substantially parallel to the first panel and extending from an interior surface of the door to substantially prevent air from flowing across the interior surface between the first air flow path and the second air flow path, a portion of the second panel to extend into the air inlet past an edge of the first panel when the door is in a fully open position. 
 
     
     
       2. The apparatus of  claim 1 , wherein the first air flow path comprises an auxiliary power unit inlet and the second air flow path comprises an auxiliary power unit cooling duct inlet. 
     
     
       3. The apparatus of  claim 1 , further comprising an actuator to actuate the door between the fully open position and a closed position. 
     
     
       4. The apparatus of  claim 1 , wherein the door further comprises opposing side panels extending from the interior surface, the second panel being positioned between the side panels. 
     
     
       5. The apparatus of  claim 4 , wherein, when the door is in the fully open position, respective ones of the opposing side panels extend into the air inlet to at least partially cover corresponding ones of corners formed between opposing lateral edges of the door and a surface surrounding the air inlet. 
     
     
       6. The apparatus of  claim 4 , wherein the opposing side panels are substantially parallel to one another and to the second panel. 
     
     
       7. The apparatus of  claim 4 , wherein the second panel includes an edge extending away from the interior surface of the door, a portion of the edge of the second panel extending further into the air inlet than corresponding portions of corresponding edges of the opposing side panels. 
     
     
       8. The apparatus of  claim 1 , wherein the second panel is offset relative the first panel to enable the second panel to be received within one of the first air flow path or the second air flow path when the door is in a closed position. 
     
     
       9. The apparatus of  claim 1 , wherein the second panel is to substantially prevent a total pressure recovery reduction for the second air flow path when the first air flow path is operating at a higher mass flow rate than the second air flow path. 
     
     
       10. The apparatus of  claim 1 , wherein the first panel is adjacent the second panel when the door is in a closed position. 
     
     
       11. A method, comprising:
 flowing air into an auxiliary power unit air inlet, the air inlet including a first air flow path and a second air flow path, the first air flow path being immediately adjacent the second air flow path, the first air flow path at least partially separated from the second air flow path by a first panel positioned within the air inlet; and 
 directing the air flow into the first air flow path and the second air flow path using a second panel oriented substantially parallel to the first panel and extending from an interior surface of an inlet door hingably coupled adjacent the air inlet, a portion of the second panel to extend into the air inlet past an edge of the first panel when the inlet door is in a fully open position. 
 
     
     
       12. The method of  claim 11 , wherein the second panel substantially prevents air from flowing across the interior surface of the inlet door between the first air flow path and the second air flow path. 
     
     
       13. The method of  claim 11 , wherein the second panel substantially prevents a total pressure recovery reduction for the second air flow path when the first air flow path is operating at a higher mass flow rate than the second air flow path. 
     
     
       14. An apparatus, comprising:
 an air inlet for an aircraft comprising a first air flow path and a second air flow path, the first air flow path at least partially separated from the second air flow path by a first panel positioned within the air inlet; and 
 a door hingably coupled adjacent the air inlet, the door comprising means for substantially preventing a total pressure recovery reduction for the second air flow path when the first air flow path is operating at a higher mass flow rate than the second air flow path, the means for substantially preventing the total pressure recovery reduction to extend into the air inlet past an edge of the first panel when the door is in a fully open position. 
 
     
     
       15. The apparatus of  claim 14 , wherein the means for substantially preventing the total pressure recovery reduction comprises a second panel extending from an interior surface of the door. 
     
     
       16. The apparatus of  claim 15 , wherein the second panel is offset relative to the first panel to enable the second panel to be received within one of the first air flow path or the second air flow path when the door is in a closed position. 
     
     
       17. The apparatus of  claim 14 , wherein the means for substantially preventing the total pressure recovery reduction is to substantially prevent air from flowing across an interior surface of the door between the first air flow path and the second air flow path. 
     
     
       18. The apparatus of  claim 14 , further comprising an actuator to actuate the door between the fully open position and a closed position. 
     
     
       19. The apparatus of  claim 14 , wherein the door further comprises opposing side panels extending from an interior surface of the door. 
     
     
       20. The apparatus of  claim 19 , wherein the means for substantially preventing the total pressure recovery reduction is positioned between the side panels. 
     
     
       21. An apparatus, comprising:
 a door selectively covering a first flow path and a second flow path, the door including:
 a first panel extending from a first side of the door, when the door is in a fully open position, the first panel to cover a first corner formed between the door and a first surface defining the first flow path; 
 a second panel extending from a second side of the door, when the door is in the fully open position, the second panel to cover a second corner formed between the door and a second surface defining the second flow path; and 
 a third panel to extend toward at least one of the first flow path or the second flow path, when the door is in the fully open position, the third panel to extend into the at least one of the first flow path or the second flow path. 
 
 
     
     
       22. The apparatus of  claim 21 , wherein the first panel, the second panel, and the third panel are substantially parallel to one another and are to be substantially parallel to corresponding surfaces defining at least one of the first flow path or the second flow path.